Rotator cuff repair with an interposition polypropylene mesh:A biomechanical ovine study

BACKGROUND Chronic large to massive rotator cuff tears are difficult to treat and re-tears are common even after surgical repair.We propose using a synthetic polypropylene mesh to increase the tensile strength of rotator cuff repairs.We hypothesize that using a polypropylene mesh to bridge the repair of large rotator cuff tears will increase the ultimate failure load of the repair.AIM To investigate the mechanical properties of rotator cuff tears repaired with a polypropylene interposition graft in an ovine ex-vivo model.METHODS A 20 mm length of infraspinatus tendon was resected from fifteen fresh sheep shoulders to simulate a large tear.We used a polypropylene mesh as an interposition graft between the ends of the tendon for repair.In seven specimens,the mesh was secured to remnant tendon by continuous stitching while mattress stitches were used for eight specimens.Five specimens with an intact tendon were tested.The specimens underwent cyclic loading to determine the ultimate failure load and gap formation.RESULTS The mean gap formation after 3000 cycles was 1.67 mm in the continuous group,and 4.16 mm in the mattress group(P=0.001).The mean ultimate failure load was significantly higher at 549.2 N in the continuous group,426.4 N in the mattress group and 370 N in the intact group(P=0.003).CONCLUSION The use of a polypropylene mesh is biomechanically suitable as an interposition graft for large irreparable rotator cuff tears.

Polypropylene versus Polyester Mesh for Laparoscopic Inguinal Hernia Repair: Short-Term Results of a Comparative Study

Background: Polypropylene meshes are commonly used in laparoscopic inguinal hernia repair, although they may cause complications. In this prospective study, a polyester mesh was compared to a polypropylene mesh. Methods: Transabdominal preperitoneal (TAPP) laparoscopic repair was performed in 160 consecutive male patients suffering from unilateral inguinal hernia. The first 80 cases received a polypropylene mesh (Parietene, Covidien, France), and a polyester mesh (Parietex, Covidien, France) was implanted in the second half of patients. Both groups were comparable with respect to clinical and demographic variables. Patients rated their pain using the visual analogue scale (VAS), and ultrasonography was performed on postoperative days 1 and 3 to measure seroma formation. Results: The duration of surgery and the length of stay were similar in both groups. Postoperative pain, measured on day 1 and 3, was significantly less in patients who had received a polyester mesh as compared to the polypropylene group. The size of local seroma was also significantly reduced in the polyester group. Complication rates were 10% in the polypropylene and 9% in the polyester group and included one early recurrence in each group. Conclusions: Polyester meshes may be useful in TAPP, as this mesh material produces less foreign body reaction with less seroma formation and lower pain levels than conventional polypropylene.

Structure and Mechanical Properties of Polypropylene Hernia Meshes with Various Weight

Polypropylene( PP) is a kind of stable material with excellent mechanical properties. Meshes made of PP have lots of obvious advantages. In this paper,5 PP hernia meshes with different warp-knitting structures which can be sorted into one light-weight hernia mesh,two standard-weight hernia meshes and two heavyweight hernia meshes were chosen to have a serious of mechanical test,including weight density,thickness,pore size,porosity,tensile strength,bursting strength,stitch tear strength,tear strength and bending rigidity. The respective relationship between mechanical performance and weight density were analyzed. The results revealed that heavy-weight hernia meshes had the biggest thickness( 0. 834 mm),the smallest pore size( 462 μm) and the smallest porosity( 58. 40%). The mechanical performance demonstrated that the tensile strength increased more than 800 N,the stitch tear strength increased more than 40 N,the bursting strength increased more than750 N and the tear strength increased more than 40 N by enlarging the weight density by 100-150 g/m^2. However, heavy-weight hernia meshes had problems of high bending rigidity,unevenness and anisotropy. Standard-weight hernia meshes with 70-140 g/m^2 not only met the demand of the mechanical properties,but also had good flexibility and structure parameters,which could be considered as an ideal hernia mesh.

Reconstruction of Partial Auricular Defects by Polypropylene Mesh Helix Framework

Background: Current techniques in partial auricular reconstruction can utilize an autologous or alloplastic framework covered by a variety of soft tissue envelopes. Objective: Is to evaluate the benefit of using polypropylene mesh to reconstruct helix framework in partial auricular defects covered with local postauricular skin flap. Method: Eleven patients with partial auricular defect were treated by using polypropylene mesh helix framework which is covered with post auricular flap in a two stage repair;clinical results of the procedure were evaluated. Results: This technique achieved satisfactory results in 9 (81.8%) cases. Early Post operative complications: Hematoma formation in one case, mild infection in two cases, edema in two cases, and Partial overlying skin breakdown in one case with failure of technique. Late Post operative complications: Hypertrophic scar in one case, narrow retroauricular sulcus in one case, hair bearing skin over the auricle in one case. Conclusion: It is a simple technique, with satisfactory clinical results, easily done, even under local anesthesia, with no donor site morbidity of autogenous cartilage harvesting, not costly as other alloplastic substitutes, large series and longer follow up period are needed for better evaluation of this technique.

Research Progress of Titanium Polypropylene Mesh in Breast Reconstruction

To investigate the application of titanium polypropylene mesh in breast reconstruction.In this study,we selected the literature data in recent 4 years to analyze the application of titanium polypropylene mesh in breast reconstruction.Using the keywords of"breast reconstruction,""titanium polypropylene mesh,^^"application"and"research progress,we analyzed and summarized the related research progress of titanium polypropylene mesh in breast reconstruction.The research was conducted using the analysis of titanium polypropylene mesh,titanium polypropylene mesh in breast reconstruction surgery advantages,adverse complications related to titanium polypropylene mesh in breast reconstruction surgery and preventive measures.By constantly improving these aspects in the research process,the current study has certain value,and may guide the research work of titanium mesh in breast reconstruction.

Dynamic Mechanical Properties of Tissue after Long-Term Implantation of Collagen and Polypropylene Meshes in Animal Models

Purpose: Pelvic floor reconstructive surgery has grown significantly in recent years. A wide variety of available types of meshes exist but the safety and success has not been adequately proven. We sought to evaluate the effects on dynamic biomechanical properties of tissue after long-term implantation of synthetic and biological grafts. Methods: A total of 96 New Zealand white female rabbits (approximately 3 kg) were used, 72 of which were surgically implanted with acellular, collagen mesh (n = 36) or nonabsorbable monofilament polypropylene mesh (n = 36). There was a no mesh-rupture of fascia group (n = 12) and a second, no-mesh, no-fascia rupture control group (n = 12). In the 59 rabbits, of 72 (13 died) tissue was harvested 3 months (n = 24), 6 months (n = 23) and 9 months (n = 12) later, while in the fascia rupture group, tissue was harvested 6 months later. Tissue samples (2 × 2 cm) underwent dynamic mechanical analysis (DMA) testing during which the dynamic rigidity and tissue damping capacities were measured. The statistical analysis was performed with General Linear Model with Tukeys post hoc testing (sPss v.17.0). Results: With respect to mesh type, the rabbit tissue in which polypropylene mesh was used showed the greatest dynamic rigidity. Those with biological mesh delivered the lowest rigidity results, while the two other groups had almost similar behavior. The meshes exhibited their highest relative dynamic tissue stiffening effect at 9 months. Conclusions: Biological mesh causes lower tissue rigidity, resulting in inferior mechanical response and thus seems to be inferior to polypropylene.

Intestinal erosion caused by meshoma displacement:A case report

BACKGROUND A meshoma formation and erosion to the small intestine is rare.Herein,we report one case of a meshoma that was not treated early;causing it to displace and erode the small intestine,with infection,complete control of symptoms was achieved after removal of the infected patch mass,no recurrence of hernia after 2 years of follow-up.CASE SUMMARY A 62-year-old male patient presented with recurrent abdominal pain repeatedly for 1 wk,which has worsened 2 d before admition,accompanied by fever.Five years before presentation he underwent right inguinal hernia Plug and patch repair approach.Two years ago,a computed tomography scan revealed a right lower abdominal mass with soft tissue density,measuring approximately 30 mm×17 mm,which was diagnosed as meshoma that was not treated.The patient had poorly controlled diabetes in the past year.CONCLUSION The formation of meshoma is rare,and that if not treated in time it might erode and require resection of the involved organ.

Establishment and evaluation of an improved rat model of open abdomen

Introduction:This study aimed to establish an animal model of open abdomen(OA)through temporary abdominal closure via different techniques.Methods:Adult male Sprague-Dawley rats were randomly divided into three groups:group A(OA with polypropylene mesh alone);group B(OA with polypro-pylene mesh combined with a patch);and group C(OA with polypropylene mesh and a sutured patch).Vital signs,pathophysiological changes,and survival rates were closely monitored in the rats for 7 days after surgery.Abdominal X-rays and histopathological examinations were performed to assess abdominal organ changes and wound healing.Results:The results showed no significant difference in mortality rates among the three groups(p>0.05).However,rats in group B exhibited superior overall condi-tion,cleaner wounds,and a higher rate of wound healing compared to the other groups(p<0.05).Abdominal X-rays indicated that varying degrees of distal intestinal obstruction in all groups.Histopathological examinations revealed fibrous hyperpla-sia,inflammatory cell infiltration,neovascularization,and collagen deposition in all groups.Group B demonstrated enhanced granulation tissue generation,neovasculari-zation,and collagen deposition compared to the other groups(p<0.05).Conclusions:Polypropylene mesh combined with patches is the most suitable method for establishing an animal model of OA.This model successfully replicated the patho-logical and physiological changes in postoperative patients with OA,specifically the progress of abdominal skin wound healing.It provides a practical and reliable animal model for OA research.

碳纤维编织网与聚丙烯水泥基复合材料加固圆柱轴压试验

完成了14个基于碳纤维编织网与聚丙烯纤维水泥基复合材料加固圆柱的轴压性能试验,得到了各试件的极限承载力与破坏形态,测得了各试件平均压应力-混凝土应变曲线、平均压应力-碳纤维编织网应变曲线及各试件极限承载力柱状图,分析了加固层水泥基复合材料中聚丙烯纤维含量、碳纤维编织网包裹层数及网格大小等参数对试件轴压性能及破坏机理的影响。试验结果表明:采用碳纤维编织网与聚丙烯纤维水泥基复合材料加固圆柱可明显提高其极限承载力;试件主要破坏形态为纵向压劈破坏,脆性破坏特征明显;加固层少量聚丙烯纤维含量(质量比0.05%,0.15%,0.25%)的改变对试件承载力的提高不明显;在一定范围内试件承载力随碳纤维编织网包裹层数的增加而提高;相比于2 cm网格碳纤维编织网,1 cm网格碳纤维编织网对试件承载力的提高效果更好。

Cost effective use of mosquito net mesh in inguinal hernia repair

Mesh hernia repair is one of the commonest open techniques of inguinal hernia repair.The main limiting factor in the use of new meshes is the cost.We carried out a prospective randomized double blind study and comprising of a hundred patients with 100 inguinal hernias admitted consecutively for elective surgery,divided into the polypropylene mesh(PPM)group and the mosquito net mesh(MNM)group each containing fifty patients.All cases were completed successfully and results revealed no difference in two groups.The results of the present study,in consistent with the published literature,reveal that the cheap indigenous mosquito mesh,which has similar properties of an imported mesh,can be safely used for tension-free inguinal hernia repair in adults.Further trials with a larger number of patients and longer follow-ups are justified and recommended.

Effects of Porosity on Structure and Performance of PP Meshes for Reparing Pelvic Floor Defects

Currently,polypropylene( PP) synthetic mesh is a kind of common material used for pelvic floor's repairing and reconstruction.The repairing mesh is generally made with different hole shape and size.Porosity is one of the most important indicators of PP mesh.Two different-structure PP meshes are selected through adopting corresponding target density in the heat setting process for meshes owning different porosity.Then performance and structure of two kinds meshes with different porosity are tested.The results showed that: the increase of porosity leaded to the decreases of meshes' thickness,tensile strength and bursting strength.Meshes' bending stiffness was reduced and they became softer,but there was no significant change in suture pulling-out force, which maybe associated with the large aperture of PP meshes.

Mesh-Related SIN Syndrome. A Surreptitious Irreversible Neuralgia and Its Morphologic Background in the Etiology of Post-Herniorrhaphy Pain

Purpose: The ubiquitous use of synthetic materials in hernia surgery has brought about a new clinical syndrome: Surreptitious Irreversible Neuralgia (SIN). It is surreptitious because it is of slow onset, unsuspected and enigmatic to clinicians;irreversible because the pain is progressive, unrelenting and unresponsive to treatment. Removal of the mesh does not guarantee pain relief. Neuralgia following mesh insertion, when it occurs, remains a poorly understood phenomenon. Methods: Ten specimens in each group: virgin tissue, scar tissue and explanted mesh from the posterior inguinal wall were examined histologically to assess nerve density, nerve size and nerve and vessel ingrowth into the deformed mesh and within its pores. Results: There was no significant difference in nerve density between virgin, scar and mesh samples. All of the explanted meshes had nerves within the scar tissue encasing the mesh (interstitial infiltration). Nerve ingrowth through the pores of the mesh (micro-entrapment) was detected in 90% of the explanted mesh specimens. Additionally, nerves were detected entrapped within the folds and deformations of mesh explants. Ingrown vessels showed congestion and focal fibrin thrombi. Conclusion: The presence of mesh does not significantly affect nerve density, while the nerves and their terminal ends are in a vulnerable position about the mesh and within its pores. These pores need to be viewed as “mini-compartments” of biological tissue where the vasculature, nerves and their receptors are exposed to potential mechanical and chemical factors: scarring, entrapment, compression, tugging, deformation, contraction, hypoxia/acidosis, inflammation and edema.

聚丙烯网水泥砂浆面层加固砖砌体结构振动台试验及数值模拟

以陕西省蓝田县的单层砖砌体结构为原型,制作了1/2缩尺的试验模型,并对其进行了聚丙烯网水泥砂浆面层加固。完成了加固模型的地震模拟振动台试验,分析加固模型的地震破坏过程及破坏形态;基于试验研究,采用ABAQUS软件建立聚丙烯网水泥砂浆面层加固砖砌体结构的有限元模型,将加固模型的动力特性、动力响应和地震损伤分布的计算结果与试验结果进行对比分析,验证了有限元模型的合理性,进而对是否加固、面层水泥砂浆强度和聚丙烯网格间距进行了参数分析。结果表明,聚丙烯网水泥砂浆面层加固砖砌体结构的破坏主要发生在门窗洞口角部、纵横墙交接处及纵墙的檩条下方;有限元模型计算结果与试验结果吻合良好,能够较好地反映加固模型在地震作用下的受力性能;聚丙烯网水泥砂浆面层加固能抑制裂缝的产生和发展,减小动力响应,有效提升砖砌体结构的抗震性能;随着面层水泥砂浆强度的提高和聚丙烯网格间距的减小,加固模型的地震损伤程度不断减轻、动力响应逐渐减小。

腹腔镜改良Dubuisson术治疗盆腔器官脱垂的临床疗效分析

目的:分析腹腔镜改良Dubuisson术治疗前、中盆腔器官脱垂的有效性及安全性。方法:回顾性收集2020年12月至2021年12月因盆腔器官脱垂行腹腔镜改良Dubuisson术的32例患者的临床资料。分析患者年龄、产次、BMI、手术时间、术中出血量、术后排气与尿管留置时间、术后住院时间及围术期、随访期并发症等,比较手术前后盆腔器官脱垂定量分期法及盆底功能影响问卷简表评分、患者主观满意度等。结果:手术均顺利完成,无中转开腹及术中并发症发生。手术时间65~240 min,平均(147.19±47.74)min;术后留置尿管1~4 d,平均(2.31±1.06)d;术后1~3 d恢复排气,平均(1.25±0.51)d;术后住院2~6 d,平均(4.41±1.04)d。术前与术后12个月盆腔器官脱垂定量分期法指示点Aa、Ba、C、Ap、Bp差异均有统计学意义(P<0.05);术后1年患者主观满意度为100%;术前与术后12个月盆底功能影响问卷评分差异有统计学意义(P<0.01)。结论:腹腔镜改良Dubuisson术是治疗前、中盆腔器官脱垂的有效术式,疗效显著,并发症发生率较低,值得学习与掌握。

聚丙烯网状平片无张力疝修补的优势及腹股沟疝气手术中的运用效果

目的分析聚丙烯网状平片无张力疝修补术治疗腹股沟疝气的效果观察;方法选择我院2020年1月至2021年10月收治的50例患有腹股沟疝气的患者进行分析,通过数字法将其分为两组,对照组行传统疝气,观察组行聚丙烯网状平片无张力疝修补术进行治疗,对比两组患者的临床指标数据;结果在对两组患者的聚丙烯网状平片无张力疝修补术以及传统的疝修补术进行对比分析后,观察组患者的治疗总有效率显著高于对照组(P<0.05);观察组患者的手术时间、住院时间、术中出血量以及治疗费用均显著优于对照组(P<0.05);观察组患者行聚丙烯网状平片无张力疝修补术并发症总发生率显著低于对照组患者行传统的疝修补术(P<0.05);结论腹股沟疝无网张力疝修补术的操作时间较短,术后复发率较低,手术更简单,可以显著改善患者的预后建议在临床中进一步推广并应用。

Tannic acid-loaded hydrogel coating endues polypropylene mesh with hemostatic and antiinflammatory capacity for facilitating pelvic floor repair

The application of polypropylene mesh(PPM)in pelvic organ prolapse(POP)treatment was severely limited by the complications associated with PPM,such as mesh exposure,chronic inflammatory reactions and postoperative hematoma.This study applied a method of fabricating a hydrogel-mesh complex(PPM+TA@GelMA)to cross-link tannic acid(TA)directly with Methacrylate Gelatin(GelMA)hydrogel and thus to form a coating for PPM.This one-step coating modification improved the hydrophilicity and cyto-compatibility of PPM.The hemostatic effect of PPMtTA@GelMA was confirmed through tail amputation test.Through the defect tissue repair experiments in vivo,it was proved that PPMtTA@GelMA had effects of anti-inflammation and promoting tissue repair and regulated the M2 subtype macrophages polarization for tissue repair.The TAloaded hydrogel coating endued PPM with multiple functions.It is believed that the novel hydrogel-mesh complex and its fabrication method will have great significance in basic research and clinical application.

Titanium-coated polypropylene mesh as innovative bioactive material in conservatives mastectomies and pre-pectoral breast reconstruction

Breast reconstruction is rapidly evolving,thanks to the growing acceptance of synthetic meshes as innovative biomaterials.276 patients undergoing mastectomy(total of 328 mastectomies)were analyzed in a retrospective observational study to evaluate the pre-pectoral immediate breast reconstruction(IBR)using an implant wrapped with Titanium-Coated Polypropylene Mesh(TCPM)vs.patients treated with tissue expander(TE),equally placed pre-pectorally(and wrapped with the same TCPM in 74.3%of the control group’breasts).163 patients,of the study group(SG),underwent mastectomy and pre-pectoral IBR with implant wrapped with TCPM,in a one-step surgery,called direct-to-implant technique(DTI),while 113 patients control group(CG)underwent mastectomy and TE.DTI technique has been performed in 192 breasts of the SG while TE procedure in 136 breasts of the CG.The BREAST-Q questionnaire has been provided before the treatment and 2 years later.Baker scale has been used to evaluate capsular contracture.Oncologic,surgical,and aesthetic outcomes along with BREAST-Q scores were analyzed.Additionally,a histologic evaluation was conducted in 11 capsules’samples randomly chosen(6 derived from SG patients and 5 derived from CG).Complications were recorded in 43 cases(29SG-14CG):8 skin-nipple necrosis(5SG-3CG),8 wound dehiscence(6SG-2CG),3 hematomas(1SG-2CG),and 24 infections(8SG-16CG).Grade IV capsular contracture was detected in 9 breasts(1SG-8CG),whereas 254 breasts were grade I(110SG-144CG),33(10SG-23CG)grade II,and 32(4SG-28CG)grade III.Implant wrinkling was detected in 18 cases(10SG-8CG)after 30 months.The local tumor recurrence rate was 5.8%.Three recurrences were on the nipple-areola complex(1.9%).SG patients showed significantly higher rates in the BREAST-Q overall Satisfaction with Outcome(74.1),overall Satisfaction with Breasts(69.1),Psychosocial Well-being(81.9),and Sexual Well-being(63.1),versus CG’s patients(p<0.05).Histological analysis showed a process of normal tissue repair with a complete mesh integration and normal healing.Conservative mastectomies with pre-pectoral IBR assisted by TCPM proved themselves oncologically safe,biologically integrated into native tissues,and highly accepted in terms of quality of life guaranteeing a more natural and aesthetic breast appearance.Core tip:This retrospective observational study provided clinical and histological outcomes of the pre-pectoral IBR using an implant wrapped with TCPM vs.patients treated with TE,equally placed pre-pectorally.The efficacy of IBR using an implant wrapped with TCPM was confirmed by the cosmetic results obtained and by a rate of side effects comparable to TE.All the histological analyses performed confirmed the TCPM mesh complete integration with the physiological aspects of healing:The Collagen 1 and 3 expressions did not differ,between TCPM and NO TCPM samples to confirm a process of healing overlapping to perfect device incorporation and normal healing.

An innovative technique of chest wall stabilization and reconstruction in traumatic flail chest:The figure-of-eight suture with polypropylene mesh and musculofascial flap

Surgical stabilization of the flail chest is challenging and has no established guidelines.Chest wall integrity and stability are the main factors that ensure the protection of intrathoracic organs and an adequate respiratory function.Here,we report a novel chest wall reconstruction technique in a 45-year-old man with a traumatic left flail chest and open pneumothorax diagnosed both clinically and radiographically.Rib approximation and chest wall reconstruction was done using intercostal figure-of-eight suture and polypropylene mesh with vascularized musculofascial flap.The patient improved gradually and was discharged after three weeks of total hospital stay.He returned to regular working after a month with no evidence of respiratory distress or paradoxical chest movement.Follow-up visit at one year revealed no lung hernia or paradoxical chest movement.This is a novel,feasible and cost-effective modification of chest wall reconstruction that can be adopted for thoracic wall repair in case of open flail chest,which needs emergency surgical interventions even in resource constraint settings.

自体腹膜覆盖聚丙烯补片抗粘连作用的实验研究

目的研究在大鼠腹腔内植入聚丙烯(polypropylene PP)补片并以补片旁腹膜覆盖后能否减少聚丙烯补片引起的腹腔粘连。方法选用SD大鼠120只,分为裸露组(A组)、转移组(B组)、翻转组(C组)及游离组(D组),将聚丙烯补片植入大鼠腹腔,以A组作为对照,B、C、D组采用不同的腹膜覆盖的方法,在术后3、7、28 d分别处死大鼠,进行大鼠腹腔内粘连程度检测、组织学检查及扫描电镜检查以了解补片表面的粘连情况。结果术后3 d,对照组A组的聚丙烯补片表面粘连较实验组B、C、D组明显(P<0.05);术后7 d及28 d,A组和D组聚丙烯补片表面粘连明显较B、C组明显(P<0.05)。术后7 d各组补片表面的粘连较3 d时明显,术后28 d时粘连与7 d时相似。补片表面没有粘连的区域术后7 d可见有腹膜覆盖。结论转移及翻转的腹膜能在聚丙烯表面存活并能减少其表面的粘连,而游离的腹膜坏死后并不能减少聚丙烯补片表面的粘连。

聚丙烯网状平片无张力疝修补术治疗36例股疝的临床体会

目的探讨股疝无张力修补术的合理修补方式。方法 36例股疝患者采用聚丙烯网状平片修补薄弱耻骨肌孔区域,封闭股环,并对此进行回顾性研究。结果 36例患者恢复良好,无近期及远期并发症,随访1~7年无股疝或腹股沟疝复发。结论合理修补股疝患者的腹壁缺损区,有利于局部解剖及生理功能的恢复。